AUTHORITIES believe the bomb maker behind the Paris terror massacre could be linked to Tuesday’s attacks in Brussels.

Belgian Najim Laachraoiui, 24, is a suspected Islamic State commander who gave authorities the slip when he returned to Syria last year, and is believed to have creatsueded explosive devices used in November massacre that killed 130 people.

With a manhunt underway in Brussels, where terror attacks killed at least 34 people and wounded around 250 on Tuesday morning, the terror suspect has emerged as a key suspect, according to reports.

A wanted notice was issued earlier in the week identifying Laachraoui as linked to the Paris attacks. He returned to attention of police after interviewing top Paris terror suspect Salah Abdeslam.

Najim Laachraoui is believed to be a key suspect in the Brussels atrocities. Picture: Belgian Federal Police/AFP PhotoSource:AFP

Police were already looking for Najim Laachraoui as part of the investigation into the Paris terrorist attacks. Picture: Belgian Fedearl Police/AFP PhotoSource:AFP

Police earlier issued a wanted notice for a suspect seen running away from the Brussels airport following the initial blast.

A CCTV image captured inside the airport at Zaventem shows a man sporting a goatee beard, wearing glasses, a white jacket and a black hat, casually pushing a trolley with a large black bag.

Authorities are on the hunt for the suspected terrorist, believed to still be at large, while two men he was seen with are believed to have carried out the airport attack.

The three men were recorded calmly strolling through the terminal before two explosions in what the federal prosecutor called a “suicide attack”. Belgian authorities have said the attackers carried bombs “in their bags”.

Eyewitness accounts have described horrifying scenes inside the airport and train station hit by three bombs over a two-hour period during rush hour. Footage from inside shows people hiding behind luggage while others ran from the building.

Belgian Federal Police have issued a wanted notice for this man, believed to be at large. Picture: Belgian Federal Police/AFPSource:AFP

Belgian police have released this CCTV footage of the suspects in Tuesday’s terror attacks. Picture: Belgian Federal Police/AFPSource:AFP

Kalashnikov rifles and a suicide belt were found in the airport, according to security officials. The city remains in lockdown with all flights and trains cancelled. People are also being advised to stay inside as the terror threat is raised to the maximum level 4.

The Islamic State has claimed responsibility for the attack which comes four days after the arrest of Paris terror suspect Salah Abdeslam in the Molenbeek district of the city.

Belgian Prime Minister Charles Michel called it a “blind, violent and cowardly” attack that marked a “tragic moment in our country’s history.”

Malcolm Turnbull is among world leaders who have pledged support.

The Prime Minister said the Australian people condemned the cowardly attacks and offered our “most resolute solidarity”.

He confirmed there had been no reports of Australians injured in Brussels.

Belgian police have been hunting for 24-year-old Najim Laachraoui since Monday when authorities issued a wanted notice for the man after interviewing Paris terror suspect Salah Abdeslam.

Following interviews with Abdeslam, Belgian prosecutors identified Laachraoui as a new accomplice in last year’s deadly Paris attacks.

Prosecutors said Laachraoui’s DNA had been found at an apartment used by the Paris attackers that he rented under a false name in Auvelais, near the central Belgian city of Namur, and at another suspected hide-out in Schaarbeek.

The former Catholic schoolboy and electromechanics students is believed to have thrown away a promising future to join the ranks of IS, and is believed to have set up at least one home bomb factory in Schaarbeek before the Paris attacks.

It is now feared he may have been the mastermind behind Tuesday’s Brussels bombings.

Similar chemicals and materials to those used in the Paris attacks are believed to have been used by the Brussels bombers, whose devices ripped through a major airport and train station.

The roof was blown off the airport and smoke billowed from the building.Source:Twitter

KALASHNIKOVS, SUICIDE BELTS REPORTED AT AIRPORT

The chaos began at the airport where it’s believed the attacks were carried out by suicide bombers and explosives inside luggage.

One explosion occurred near the American Airlines check in desk followed quickly by a second that was said to have taken place near a Starbucks at the exit. A US security official who wasn’t authorised to speak publicly said it’s believed there was at least one suitcase bomb.

Federal prosecutor Frederic Van Leeuw called all three explosions “terrorist attacks” and said they were probably carried out by a “suicide bomber”.

WORLD LEADERS RALLY

Leaders have united in a show of solidarity after the attack. Belgian Prime Minister Charles Michel said “absolute priority goes to the victims”.

“We realise we face a tragic moment. We have to be calm and show solidarity,” he said.

French Prime Minister Manuel Valls said Europe was at war and had been for the last few months. UK Prime Minister David Cameron tweeted his condolences and said “we will never let these terrorists win” from Downing Street.

The terrorists behind today’s atrocities attack our way of life and they attack us because of who we are. We will never let them win.

Australian leader Malcolm Turnbull also took to Twitter, while European Union president Donald Tusk said he was appalled by the bombings in the city where the EU is based.

“These attacks mark another low by the terrorists in the service of hatred and violence.”

Swedish Prime Minister Stefan Lofven said they were “an attack against democratic Europe.”

“We will never accept that terrorists attack our open societies,” he told news agency TT in a statement, while his Danish counterpart Lars Lokke Rasmussen denounced the blasts on Twitter as “despicable”.

President Obama was briefed on the situation from Cuba and said the US will do “whatever is necessary” to support their ally. Russian President Vladimir Putin called for countries to unite to fight terror, while Pope Francis has also condemned the attack and offered prayers for victims.

Deeply concerned by the attacks in Brussels. Australians' thoughts, prayers & solidarity are with the people of Belgium.

Prime Minister Malcolm Turnbull has confirmed there have been no reports of Australians injured in the attacks, and has offered Austraila’s support.

“Australians condemn these cowardly attacks in Brussels, and the people of Brussels have our thoughts and our prayers with them, but above all our most resolute solidarity,” he told the Nine Network.

After meeting with the federal police commissioner, ASIO chief and Attorney General, Mr Turnbull said he had been advised there was no requirement to increase Austraila’s terrorism threat advisory from its current level of probable. He said there was already a high level of security at airports.

“We are in a much stronger position from a security point of view (compared to Brussels),” he said.

Mr Turnbull said though it was “early days”, the government was “not aware of any Australians being involved” in events in Brussels.

Malcolm Turnbull spoke about Australia’s response to the attacks on Today.Source:Channel 9

Australia’s finance minister, Belgian-born Mathias Cormann, said it was a “black day” for his home country.

“I’ve been to all those places, I walked along those streets many times and it is quite confronting,” he told ABC Radio.

Mr Cormann said though the people of Belgium are in “deep shock”, he had also felt a sense of defiance while speaking with friends and family back home.

“People in Belgium and people across Europe don’t want to let this atrocity get them down. they are very determined to press ahead and essentially enjoy their life,” he said.

JOURNALIST DESCRIBES AIRPORT SCENE

Sky News journalist Alex Rossi was inside the airport at the time and said it was incredibly confused.

“Don’t know about the number of injuries but certainly, the people I am with believe there is a terrorist attack, but again cannot confirm,” he said.

He told Sky News he could feel the building move with dust and smoke surrounding him.

“I went towards where the explosion came from and there were people coming out looking very dazed and shocked.

“The thinking here is that it is some kind of terrorist attack although that hasn’t been verified by any of the authorities here at the airport.”

Mia Egerton-Warburton is trapped in the city with friends Dilusha Jayasekara, from Melbourne, Ellie Rose from Sydney and Jyotsna Singh from Sydney.Source:Supplied

The Belgian capital has become a hotbed of radicalisation in recent years, with more jihadist per capita than any other country. Of the 11 million citizens, around 500 have left for Syria with many going to Islamic State, Al-Nusra or Al-Qaeda, with up to 40 of them from the Molenbeek area where Salah Abdeslam was found hiding last week.

Airports in London, Prague, Amsterdam, Vienna, and many others, have increased security following the attacks. British and French Prime Ministers are holding emergency meetings and the UK’s Gatwick Airport, Heathrow and London Underground have also increased security.

Russian Transport Minister Maxim Sokolov tells Russian news agencies that authorities will re-evaluate security at Russian airports, which were subject to a terror attack in 2011.

Germany’s Deutsche Bahn has also cancelled its high speed service to Brussels and leaders from Holland, Spain and Austria have pledged their support for Brussels.

More than 200 flights have been cancelled so far and authorities are warning people against making non-essential calls to avoid burdening the phone network.

Passengers wait at the entrance to the Eurostar in London after services were disrupted in the wake of the attacks. Picture: Dan Kitwood/Getty Images.Source:Getty Images

Passengers are evacuated from Brussels airport. Picture: John Thys/AFPSource:AFP

TRAIN EVACUATED IN AMSTERDAM

Police in the Netherlands have stopped an international train and are searching passengers at the Hoofddorp station, which has been evacuated.

Authorities have not revealed what has caused them to stop the train but there has been no arrests reported.

Meanwhile hundreds of stranded passengers have gathered at a sports hall in Zaventem. Twenty-two year old butcher Henry Dewespelaere said they are waiting on further instructions on what to do with people.

The blown out windows of Zaventem airport. Picture: Peter Dejong/APSource:AP

Tributes to the victims have poured in across social media, with thousands sharing pictures of red-haired reporter TinTin crying as a symbol inspired by the Je Suis Charlie moment from January 2015. TinTin’s creator was Belgian cartoonist Herge.

Others shared #JeSuisBruxelles or drew messages of love in the pavement at Place de la Bourse, where a makeshift memorial has popped up.

Flowers at a makeshift memorial at Place de la Bourse in Brussels. Picture: Kenzo Tribouillard/AFPSource:AFP

LANDMARKS LIGHT UP IN SOLIDARITY

Some of Europe’s best-known monuments have been illuminated in Belgium’s national colours in a vibrant show of solidarity after the attacks in Brussels.

As night fell on Tuesday, the Eiffel Tower in Paris was lit up in the black, yellow and red colours of the Belgian flag.

Berlin’s Brandenburg Gate and Rome’s Trevi Fountain are among other major landmarks to mark tribute with a show of Belgium’s national colours.

The Eiffel Tower is illuminated with the Belgium national colours black, yellow and red. Picture: Thibault Camus/AP PhotoSource:AP

photo galleryIn photos: Brussels attacks

Passengers are evacuated from Zaventem Bruxelles International Airport after a terrorist attack on March 22, 2016 in Brussels, Belgium. Picture: Sylvain Lefevre/Getty Images1 of 37

A plume of smoke rises over Brussels airport after the controlled explosion of a third device in Zaventem Bruxelles International Airport after a terrorist attack on March 22, 2016 in Brussels, Belgium. Picture: Sylvain Lefevre/Getty Images2 of 37

In this image provided by the Belgian Federal Police in Brussels on Tuesday, March 22, 2016 of three men who are suspected of taking part in the attacks at Belgium’s Zaventem Airport. These two men (who were accompanied by a third) in the photo that the police issued were according to a the Belgian Prosecutors ‘probably’ suicide bombers. Bombs exploded at the Brussels airport and one of the city’s metro stations Tuesday, killing and wounding scores of people, as a European capital was again locked down amid heightened security threats. Picture: Belgian Federal Police via AP3 of 37

In this image provided by the Belgian Federal Police in Brussels on Tuesday, March 22, 2016, a man who is suspected of taking part in the attacks at Belgium’s Zaventem Airport and is being sought by police. Picture: Belgian Federal Police via AP4 of 37

Two explosions have gone off at Zavantem airport in Brussells causing unconfirmed numbers of dead and injuries. Picture: Twitter5 of 37

Two explosions at Brussels Airport at the American Airlines Check in. Picture: Twitter6 of 37

This view taken on March 22, 2016 shows the broken glasses at Brussels Airport in Zaventem after a two explosions targeted the main hall. Picture: AFP PHOTO / BELGA / JONAS ROOSENS7 of 37

In this photo provided by Ralph Usbeck a police officers directs passengers in a smoke filled terminal at Brussels Airport, in Brussels after explosions Tuesday, March 22, 2016. Picture: Ralph Usbeck via AP8 of 37

Another image provided by Ralph Usbeck shows an unidentified traveller lying on the ground in a smoke filled terminal at Brussels Airport, in Brussels, after explosions Tuesday, March 22, 2016. Picture: Ralph Usbeck via AP9 of 37

Injured and bloody people escape Brussels airport following the explosions. Picture: Twitter10 of 37

Inside the terminal: this image shows the power of the blasts. Picture: Twitter11 of 37

People are evacuated from Brussels Airport, in Zaventem, on March 22, 2016. Picture: AFP PHOTO / Belga / VIRGINIE LEFOUR12 of 37

A victim receives first aid by rescuers, on March 22, 2016 near Maalbeek metro station in Brussels, after a blast at this station near the EU institutions caused deaths and injuries. Picture: AFP PHOTO / EMMANUEL DUNAND13 of 37

A private security guard helps a wounded women outside the Maalbeek metro station in Brussels on March 22, 2016 after a blast at this station located near the EU institutions. Belgian firefighters said at least 26 people had died after “enormous” blasts rocked Brussels airport and a city metro station today, as Belgium raised its terror threat to the maximum level. Picture: AFP PHOTO / Michael VILLA16 of 37

German police officers guard a terminal of the airportthe in Frankfurt, Germany, during tighter security measures Tuesday, March 22, 2016, when various explosions hit the the Belgian capital Brussels killing several people. Picture: AP Photo/Michael Probst17 of 37

A man with blood stains on his sweater leaves Brussels airport in Zaventem on March 22, 2016 following twin blasts. Picture: AFP PHOTO / Belga / DIRK WAEM18 of 37

In this still image taken from video from TV station RTL, people receive treatment in the debris strewn terminal at Brussels Airport, in Brussels after explosions Tuesday, March 22, 2016. Picture: RTL via AP19 of 37

In this photo provided by Georgian Public Broadcaster and photographed by Ketevan Kardava a man is wounded in Brussels Airport in Brussels, Belgium, after explosions were heard Tuesday, March 22, 2016. Picture: Ketevan Kardava/ Georgian Public Broadcaster via AP20 of 37

People tending to each other immediately after the explosions: The scene in Brussels Airport in Brussels, Belgium, after explosions were heard Tuesday, March 22, 2016. Picture: Ketevan Kardava/ Georgian Public Broadcaster via AP21 of 37

This image shows people lying on the floor after a blast inside Brussels airport in Zaventem. Picture: AFP PHOTO / RTL22 of 37

WARNING: GRAPHIC IMAGE. Aftermath and terror of the bomb attack at the Maelbeek Metro station in Brussels, the image is being circulated by Belgian media but is not yet verified. Picture: Twitter24 of 37

Smoke seen after an explosion outside Maalbek Metro Station following the earlier explosion at Brussels Zaventem Airport. Source: Twitter25 of 37

A video grab made on March 22, 2016 shows metro commuters being evacuated from a subway train in Brussels, after an explosion at the Maalbeek station. A series of apparently coordinated explosions ripped through Brussels airport and a city metro station Picture: AFP PHOTO26 of 37

An injured person lay on the ground outside Maalbek Metro Station. Smoke can still be seen billowing out of the building. Source: Twitter27 of 37

Emergency rescue workers stretcher an unidentified person at the site of an explosion at a metro station in Brussels, Belgium, March 22, 2016. Picture: APTN via AP31 of 37

People walk towards the illuminated Eiffel Tower illuminated with the Belgium national colors black, yellow and red in honor of the victims of the today’s attacks at the airport and the metro station in Brussels, in Paris, Tuesday, March 22, 2016. Picture: AP Photo/Thibault Camus32 of 37

Rescue teams evacuate wounded people outside the Maalbeek metro station in Brussels on March 22, 2016 after a blast at this station located near the EU institutions. Picture: AFP PHOTO33 of 37

Solidarity messages are written in chalk outside the stock exchange in Brussels on Tuesday, March 22, 2016. Picture: AP Photo/Geert Vanden Wijngaert35 of 37

People hold up a banner as a mark of solidarity at the Place de la Bourse following today’s attacks on March 22, 2016 in Brussels, Belgium. Picture: Carl Court/Getty Images36 of 37

A writing on the asphalt reads “Brussels forever” at the place de la Bourse in the center of Brussels, where people write hundreds of messages on the ground to remember the victims of todays attack, Tuesday, March 22, 2016. Picture: AP Photo/Martin Meissner37 of 37

Passengers are evacuated from Zaventem Bruxelles International Airport after a terrorist attack on March 22, 2016 in Brussels, Belgium. Picture: Sylvain Lefevre/Getty Images

A plume of smoke rises over Brussels airport after the controlled explosion of a third device in Zaventem Bruxelles International Airport after a terrorist attack on March 22, 2016 in Brussels, Belgium. Picture: Sylvain Lefevre/Getty Images

In this image provided by the Belgian Federal Police in Brussels on Tuesday, March 22, 2016 of three men who are suspected of taking part in the attacks at Belgium’s Zaventem Airport. These two men (who were accompanied by a third) in the photo that the police issued were according to a the Belgian Prosecutors ‘probably’ suicide bombers. Bombs exploded at the Brussels airport and one of the city’s metro stations Tuesday, killing and wounding scores of people, as a European capital was again locked down amid heightened security threats. Picture: Belgian Federal Police via AP

In this image provided by the Belgian Federal Police in Brussels on Tuesday, March 22, 2016, a man who is suspected of taking part in the attacks at Belgium’s Zaventem Airport and is being sought by police. Picture: Belgian Federal Police via AP

Two explosions have gone off at Zavantem airport in Brussells causing unconfirmed numbers of dead and injuries. Picture: Twitter

Two explosions at Brussels Airport at the American Airlines Check in. Picture: Twitter

This view taken on March 22, 2016 shows the broken glasses at Brussels Airport in Zaventem after a two explosions targeted the main hall. Picture: AFP PHOTO / BELGA / JONAS ROOSENS

In this photo provided by Ralph Usbeck a police officers directs passengers in a smoke filled terminal at Brussels Airport, in Brussels after explosions Tuesday, March 22, 2016. Picture: Ralph Usbeck via AP

Another image provided by Ralph Usbeck shows an unidentified traveller lying on the ground in a smoke filled terminal at Brussels Airport, in Brussels, after explosions Tuesday, March 22, 2016. Picture: Ralph Usbeck via AP

Injured and bloody people escape Brussels airport following the explosions. Picture: Twitter

Inside the terminal: this image shows the power of the blasts. Picture: Twitter

People are evacuated from Brussels Airport, in Zaventem, on March 22, 2016. Picture: AFP PHOTO / Belga / VIRGINIE LEFOUR

A victim receives first aid by rescuers, on March 22, 2016 near Maalbeek metro station in Brussels, after a blast at this station near the EU institutions caused deaths and injuries. Picture: AFP PHOTO / EMMANUEL DUNAND

A private security guard helps a wounded women outside the Maalbeek metro station in Brussels on March 22, 2016 after a blast at this station located near the EU institutions. Belgian firefighters said at least 26 people had died after “enormous” blasts rocked Brussels airport and a city metro station today, as Belgium raised its terror threat to the maximum level. Picture: AFP PHOTO / Michael VILLA

German police officers guard a terminal of the airportthe in Frankfurt, Germany, during tighter security measures Tuesday, March 22, 2016, when various explosions hit the the Belgian capital Brussels killing several people. Picture: AP Photo/Michael Probst

In this still image taken from video from TV station RTL, people receive treatment in the debris strewn terminal at Brussels Airport, in Brussels after explosions Tuesday, March 22, 2016. Picture: RTL via AP

In this photo provided by Georgian Public Broadcaster and photographed by Ketevan Kardava a man is wounded in Brussels Airport in Brussels, Belgium, after explosions were heard Tuesday, March 22, 2016. Picture: Ketevan Kardava/ Georgian Public Broadcaster via AP

People tending to each other immediately after the explosions: The scene in Brussels Airport in Brussels, Belgium, after explosions were heard Tuesday, March 22, 2016. Picture: Ketevan Kardava/ Georgian Public Broadcaster via AP

This image shows people lying on the floor after a blast inside Brussels airport in Zaventem. Picture: AFP PHOTO / RTL

WARNING: GRAPHIC IMAGE. Aftermath and terror of the bomb attack at the Maelbeek Metro station in Brussels, the image is being circulated by Belgian media but is not yet verified. Picture: Twitter

Smoke seen after an explosion outside Maalbek Metro Station following the earlier explosion at Brussels Zaventem Airport. Source: Twitter

A video grab made on March 22, 2016 shows metro commuters being evacuated from a subway train in Brussels, after an explosion at the Maalbeek station. A series of apparently coordinated explosions ripped through Brussels airport and a city metro station Picture: AFP PHOTO

An injured person lay on the ground outside Maalbek Metro Station. Smoke can still be seen billowing out of the building. Source: Twitter

Emergency rescue workers stretcher an unidentified person at the site of an explosion at a metro station in Brussels, Belgium, March 22, 2016. Picture: APTN via AP

People walk towards the illuminated Eiffel Tower illuminated with the Belgium national colors black, yellow and red in honor of the victims of the today’s attacks at the airport and the metro station in Brussels, in Paris, Tuesday, March 22, 2016. Picture: AP Photo/Thibault Camus

Rescue teams evacuate wounded people outside the Maalbeek metro station in Brussels on March 22, 2016 after a blast at this station located near the EU institutions. Picture: AFP PHOTO

Solidarity messages are written in chalk outside the stock exchange in Brussels on Tuesday, March 22, 2016. Picture: AP Photo/Geert Vanden Wijngaert

People hold up a banner as a mark of solidarity at the Place de la Bourse following today’s attacks on March 22, 2016 in Brussels, Belgium. Picture: Carl Court/Getty Images

A writing on the asphalt reads “Brussels forever” at the place de la Bourse in the center of Brussels, where people write hundreds of messages on the ground to remember the victims of todays attack, Tuesday, March 22, 2016. Picture: AP Photo/Martin Meissner

1 of 37

Do you know more? Email victoria.craw@news.com.au and elizabeth.burke@news.com.au

Attack on Terror50:05

Explosive experts introduce us to the cutting edge technology of counter-terrorism weaponry, in a bid to free the world from the clutch of terrorist attacks.